Journal of Dental Research, Vol 72, 1391-1397, Copyright © 1993 by International & American Associations for Dental Research Online Journals
An in vitro stimulation of the effects of chewing sugar-free and sugar-containing chewing gums on pH changes in dental plaque
L. M. Macpherson and C. Dawes
Department of Oral Biology, Faculty of Dentistry, University of Manitoba, Winnipeg, Canada.
The objective of these studies was to simulate the effect of chewing
sugar-free and sucrose-containing chewing gums on the return of the pH to
neutrality after exposure to sucrose of plaque located on the buccal (BLM)
and lingual (LLM) surfaces of the lower molar teeth. In study 1, a
0.5-mm-deep artificial plaque containing Streptococcus oralis cells was
exposed to 10% sucrose for one min, and a 0.1-mm-thick film of sucrose-free
artificial saliva was then flowed over the plaque surface at the
unstimulated salivary film velocities previously found at the BLM and LLM
sites. At the time of the pH minimum (pH 4-5), one of three conditions was
simulated: (a) a no-gum-chewing control, or chewing for 20 min on either
(b) a sugar-free gum or (c) a sucrose-containing gum. The recovery of the
plaque pH to resting values was rapid during simulation of chewing a
sugar-free gum (SFG), much slower with the no-gum control, and even slower
with simulation of chewing a sucrose-containing gum (SCG). The pH recovery
was slower with the BLM than the LLM plaque. In study 2, the BLM plaque was
exposed to a 2% sucrose solution for 20 min under stimulated salivary
conditions, to simulate the consumption of a meal, followed by one of
conditions (a), (b), or (c) described above. The pH recovery with
simulation of chewing a SCG was faster than with the no-gum control, but
much slower than with the SFG simulation.(ABSTRACT TRUNCATED AT 250 WORDS)
